Several types of rolling stands with three working rolls are known for rolling tubular seamless bodies with mandrel or for rolling rod-shaped bodies in general. Said working rolls are fixed inside a roll-holding cartridge that allows the concurrent extraction of the three rolls from the rolling mill, transversally to the rolling axis, both in the case of a change of rolls for normal maintenance, and in the case of stuck when the tube itself, sometimes with the mandrel therein, must be removed from the rolling mill.
A known rolling stand includes, for each working roll:                a hydraulic capsule for adjusting the radial position of the working roll with respect to the rolling axis of the rolling mill;        a spindle, such as a toothed or Cardan spindle, for transmitting the rotation motion to the roll;        a motor and a gearbox, arranged upstream of the spindle and connected thereto.        
Before removing the roll-holding cartridge from the rolling stand it is necessary to disconnect the hydraulic capsules and the spindles from their respective working rolls.
In order to both carry the roll-holding cartridge, by moving the cartridge by means of an overhead crane, and rotate the cartridge by means of a cartridges-turning machine within the roll workshop, it is currently necessary to keep the rolls fixed with respect to the cartridge to prevent a displacement thereof during the transfer to another location. The fixing of the rolls in the cartridge in transport position, for example, is done by manually inserting some stops, suitable for blocking the roll chocks within the cartridge. These stops, such as pins that are engaged with interferences to the chocks, prevent the risk of sudden movements or downfalls of the chocks during the movement of the cartridge.
However, the fact of having to assemble, and then manually remove these stops is a long and complex operation that requires the use of many workers, in any case subjected to a dangerous activity, considering the weight and the dimensions of the mechanical parts to be managed, and the temperatures at which parts of the stands are.
The need of providing a rolling stand that allows the above drawbacks to be overcome is therefore felt.